Cerebral cortex capillaries

Galea, E. and Estrada, C., Periendothelial acetylcholine synthesis and release in bovine cerebral cortex capillaries, J. Cereb. Blood Flow Metah, 11(5), 868, 1991. 

In addition molecules have been identified on continuous endothelium that facilitate binding of albumin to endothelium, increase capillary permeability, and theoretically can increase paracellular transport or transcytosis of albumin-bound molecules. An example of this is the gp60 albumin-binding glycoprotein molecule identified on continuous endothelium in multiple tissues (heart, lung, skeletal muscle, adipose, peritoneum, and intestinal smooth muscle) but absent from continuous endothelium in cerebral cortex, and sinusoidal or fenestrated endothelium in liver, adrenal, pancreas, and intestinal lamina propria [21,22],... 

Tissue Location and Role of Aldose Reductase in Animal Models of Diabetic Complications. Aldose reductase (AR) has been located immunohistochemically in many tissues of the dog and rat, most notably, in corneal epithelium, retina, optic nerve, kidney papillae, aortic endothelium and smooth muscle cells as well as peripheral nerve and lens. AR has also been measured in human and monkey retinal mural cells. These cells are thought to provide the structural support for retinal capillaries and their loss is the first abnormality seen in clinical diabetic retinopathy. In addition, AR-like activity has been reported in a human retinoblastoma cell line and sorbinil inhibits this activity in these cells. Finally, a recent report has demonstrated that AR is present in isolated capillaries from bovine retina and cerebral cortex. Therefore, AR appears to be present in all tissues which are uniquely susceptible to deterioration during prolonged exposure to the hyperglycemia of diabetes. Accumulation of the products of the polyol pathway, sorbitol and fructose, has been demonstrated in these tissues and, where tested, sorbinil and other AR inhibitors have been shown to inhibit this accumulation. 

Hamel et al. [53] carried out northern blot hybridisation studies and demonstrated the presence of 5-HTn3 mRNA in bovine caudate nucleus and cerebral cortex, and in human cerebral cortex. 5-HTjo receptor hybridisation was not observed with RNA extracts from pial vessels in either species. Hybridisation with the 5-HTidp receptor probe revealed the presence of mRNA transcripts in both human smd bovine cerebral tissue and pial vessels. This work indicating the presence of 5-HT,Dp, but not 5-HTip , receptor mRNA in bovine and human cerebral arteries located outside the brain parenchyma, but neither type in intraparenchymed microvessels or capillaries suggests that the anti-migraine effects seen with sumatriptan, if vascular related, are probably mediated via 5-HTii, receptors. 

In anoxic-ischaemic lesions of the rat cerebral cortex, pericytes which surround many of the larger capillaries did not swell, but became compressed between the endotheUum and the neuropil (Hills 1964). 

In a longterm dosing experiment (1.8% lead acetate in the diet, from 8 days before parturition till 3 months of age), Reyners et al. (1976), showed that the capillaries of the cerebral cortex of dosed neonate rats significantly increased, while the thickness of the cortex reduced progressively. In a later paper these authors reported that the absolute number of cortical capillaries was not modified by lead (Reyners et al., 1979). They concluded that quantitative changes in the vascular supply represented a sequel to a primary effect on grey matter. This is in conflict with the conventional interpretation, i.e. that the neuronal changes observed are the result of a vascular upheaval. 

Zhang X, Rauch A, Lee H, Xiao H, Rainer G, Logothetis NK. Capillary hydrophilic interaction chromatography/mass spectrometry for simultaneous determination of multiple neurotransmitters in primate cerebral cortex. Rapid Comm Mass Spec RCM 2007 21 3621-8. 

The brain, located in the cranial cavity, is made up of three main parts cerebrum, cerebellum, and brainstem. The cerebrum is the largest part of the human mature brain, which comprises left and right cerebral hemispheres with the corpus callosum between them. The outermost surface of the cerebral hemispheres is a 2-4 mm thick folded layer, named the cerebral cortex that is also called grey matter as it consists of neuronal cell bodies, glial cells, and capillaries showing dark in colour. By contrast, the underlying tissue in the cerebrum is called white matter which consists of the white myelinated sheaths of neuronal axons. 

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